Hypericibacter terrae gen. nov., sp. nov. and Hypericibacter adhaerens sp. nov., two new members of the family Rhodospirillaceae isolated from the rhizosphere of Hypericum perforatum

Abstract

Two strains of the family Rhodospirillaceae were isolated from the rhizosphere of the medicinal plant Hypericum perforatum. Cells of both strains were Gram-stain-negative, motile by means of a single polar flagellum, non-spore-forming, non-capsulated, short rods that divided by binary fission. Colonies were small and white. Strains R5913T and R5959T were oxidase-positive, mesophilic, neutrophilic and grew optimally without NaCl. Both grew under aerobic and microaerophilic conditions and on a limited range of substrates with best results on yeast extract. Major fatty acids were C19 : 0 cyclo ω8c and C16 : 0; in addition, C18 : 1ω7c was also found as a predominant fatty acid in strain R5913T. The major respiratory quinone was ubiquinone 10 (Q-10). The DNA G+C contents of strains R5913T and R5959T were 66.0 and 67.4 mol%, respectively. 16S rRNA gene sequence comparison revealed that the closest relatives (<92 % similarity) of the strains are Oceanibaculum pacificum MCCC 1A02656T, Dongia mobilis CGMCC 1.7660T, Dongia soli D78T and Dongia rigui 04SU4-PT. The two novel strains shared 98.6 % sequence similarity and represent different species on the basis of low average nucleotide identity of their genomes (83.8 %). Based on the combined phenotypic, genomic and phylogenetic investigations, the two strains represent two novel species of a new genus in the family Rhodospirillaceae , for which the name Hypericibacter gen. nov. is proposed, comprising the type species Hypericibacter terrae sp. nov. (type strain R5913T=DSM 109816T=CECT 9472T) and Hypericibacter adhaerens sp. nov. (type strain R5959T=DSM 109817T=CECT 9620T).

Competition-cooperation in the chemoautotrophic ecosystem of Movile Cave: first metagenomic approach on sediments

“…The RuBisCO enzyme presence and the lack of genes for the photosynthetic reaction center ( pufLM ) are intriguing for Rhodospirillaceae -like bacteria. Rhodospirillaceae are known as photoautotrophic, photoheterotrophic, and chemoheterotrophic bacteria [ 69 ], but not as chemoautotrophs. Since the sulfite dehydrogenase ( soeA ) subunit was also annotated, the Dongiales -affiliated MAG may be a chemolithoautotrophic bacterium that fix CO 2 and uses sulfur compounds as electron sources.…”

Comparative Genomics and Physiological Investigations Supported Multifaceted Plant Growth-Promoting Activities in Two Hypericum perforatum L.-Associated Plant Growth-Promoting Rhizobacteria for Microbe-Assisted Cultivation

“…nov. and Hypericibacter adhaerens sp. nov. of the Rhodospirillaceae family, were also harnessed from the rhizosphere of 1.5-year-old H. perforatum plants, although their plant growth-promoting activities were not evaluated ( 35 ). This variability in H. perforatum ’s rhizobacterial composition might be attributable to the disparity in factors such as criteria and methodology of screening, geographical location, soil edaphic properties, vegetation type, and land use history, which drive the deterministic rhizomicrobial community structure ( 36 ).…”

Competition-cooperation in the chemoautotrophic ecosystem of Movile Cave – first metagenomic approach on sediments

“…The RuBisCO enzyme presence and the lack of genes for the photosynthetic reaction center ( pufLM ) are intriguing for Rhodospirillaceae -like bacteria. Rhodospirillaceae are known as photoautotrophic, photoheterotrophic and chemoheterotrophic bacteria [69], but not as chemoautotrophs. The Dongiales -affiliated MAG may be a chemolithoautotrophic bacteria that fix CO 2 and uses sulfur compounds as electron sources since the sulfite dehydrogenase ( soeA ) subunit was also annotated in the genome.…”